Dynamometer



March 23, 1954 BENNETT 2,672,954

DYNAMOMETER Filed Sept. 23, 1947 2 Shee ts-Sheet 1 Jig. 1

INVENTOR. a/"0/d L. Benneff BY T ATTORNEYS March 23, 1954 BENNETT2,672,954

DYNAMOMETER Filed Sept. 25, 1947 INVENTO Harold L. Ben/1e 7 ATTORNEYS-within a stator casing connected together, to which casing is connected-a torque arm 29.

and affords reaction vanes :stator cups too, far outwardly, provisionsmust be made to lessen t e d l??? thereof and to insure maximum effecttherefrom, while at the same time serving, by the ejector effect of thetoroidal circulation past an aperture, to eject resistance liquid fromthe coolant conduit space to rejoin the main toroidal circulation, andthereby to make room for discharge of additional heated resistanceliquid over the coolant coils, and to increase the circulation rate ofthe resistance liquid over the coolant coils.

It is also an object to provide a structure and arrangement of partswhich is mechanically simple and inexpensive, and well suited to theends in view, having in mind such factors as the necessity of admittingand discharging coolant liquid from the coils, of .admitting resistanceliquid to, and of buiding up a pressure adjacent the discharge from, thestator casing, in order to vary the load, and of admitting ordischarging air in order that the interior of the casing be notair-locked, and similar factors.

In the drawings the invention is shown in typical forms of construction,such as are presently preferred by me.

Figure 1 is in general an axial sectional view through a preferred formof the dynamometer, and Figures 2 and 3 are sections, respectively, onthe lines 22 and 3-3 of Figure 1.

Figure 4 is a half-sectional view corresponding generally to Figure 1,and illustrating a different form of construction.

No attempt is made in the present drawings to show all structural oroperational features of the 'dynamometer, for such themselves wellknown, 'tails, if desired, may be ascertained from the dynamometers arein and such structural de- No. 2,428,005, or It will parent application,now Patent bearings 30, and disposed 2 formed in two halves a shaft 3,supported by The rotor has a plurality of radially disposed vanes H,angled with respect to the axis, and the stator has a similar set ofvanes 2|, similarly disposed and angled. The

vanes H and 2! and the cups which they define in the rotor and stator,respectively, are generally complemental and afford space within whichthe toroidal circulation of resistance liquid within the stator casingtakes place.

The vanes of the stator extend radially outwardly beyond the peripheralrim In of the rotor I, and then axially inwardly to overlie the rim l0.As is explained more fully in Patent No. 2,428,005, the discharge oftoroidally circulating resistance liquid from the rotor cups, at therotors periphery especially at high speeds, is substantially radiallyoutwardly, and such overhang of the stator vanes intercepts even suchradially thrown liquid, to absorb its force (which, incidentally,produces the heat which must be dissipated), and cups to guide itscirculation again inwardly, in the general toroidal path. This thestator vanes and cups do satisfactorily, however, only if the radiallyoutward flow in the stator cups does not dominate and reverse theradially inward flow which is an essential part of the general toroidalpath. In practice this means that the radially outermost surface of thestator cups must not be spaced too greatly radially beyond theperipheral rim l0 of the rotor.' Certain factors herein which relate tothe cooling arrangements tend to extend the wherefore other withoutinterfering with-indeed, with actual assistance to-the coolingarrangements.

Whereas in the parent Patent No. 2,428, the cooling was accomplished bycirculation of a coolant through a water jacket, or, as shown herein inFigure 4, by its circulation through coils 4 within the stator casing,the coils as shown are of limited radial depth, and while they would notunduly displace radially the outside of the stator cups relative to therotor cups, neither will they afford as much cooling capacity as may beneeded with dynamometers of high absorptive capacity. Several banks ofcoils 4, arranged in radial depth in the space outside the rotorsperiphery, are preferable, but, so situated, they tend to displace toofar outwardly the outer ends of the stator cups, since into these statorcups the cooled resistance liquid must withdraw. Means, in the form ofcurved baflles 22, must be employed to form, as it were, a false bottomfor each stator cup, to intercept resistance liquid thrown radiallyoutwardly from the rotor peripheral rim H), to direct it again radiallyinwardly, and to maintain normal toroidal circulation with the liquid s0intercepted. The baflles, properly arranged have the further function ofserving, by ejector action, to withdraw cooled resistance liquid fromthe space surrounding the coils 4, and to restore it to circulation inthe normal toroidal path, with the uncooled, bafile-intercepted liquid.

The cooling conduit 4, of several coils or tubes, with its headers 4iand 62, one for inlet and the other for outlet of coolant liquid, islocated, generally speaking, within some part of the circulation path ofthe resistance liquid. In the preferred form of Figures 1 to 3 inclusivethe cooling conduit 4 is located in a by-pass from the normal toroidalcirculation path of the resistance liquid. More specifically, it islocated radially outwardly from, and peripherally surrounds, the rim ll)of the rotor l. The resistance liquid, or some part thereof, gainsaccess to the exterior of the coolant conduit by way of a series ofradial apertures l2 in the periphery In, from the individual rotor cups.Usually an appreciable part of the resistance liquid from each rotor cupdischarges past the rim of the rotors periphery, avoiding discharge fromthe apertures i2, but there are enough such apertures (though notnecessarily one in each cup) to insure a substantial discharge therefromover the cooling conduit l.

The curved baflles 22 already explained, serve in each stator cup, as tointercept and direct and thus to maintain the normal toroidalcirculation. These baffles 22 overlie the peripheral rim of the rotor,to intercept all rim discharge, and lie closely enough to the rotorsrim, and are curved inwardly to such extent, that they direct inwardly,in the normal toroidal path, all such rim discharge.

Additionally, each such baflle 22 is spaced from the outer wall of thestator cup to define a passageway 23, leading from the cooling conduitspace inwardly to the central interior of the stator cup; moreover, thispassageway 23 'progressively narrows down, and the normal toroidalcirculation passes over its narrow outlet. It follows that an ejector 0rjet action occurs at' each such outlet, serving to suck cooled resistance liquid away from the cooling conduit 4, and to make room forheated resistance liquid about the cooling conduit. The so-withdrawncooled resistance liquid mingleswith the toroidsally eircrlatinerrcistancaliquidhccohne. it; which gliher lefilllb This-mmeess i r eneaten. zcvcrrranidlr auspices: herccciactzi ulate rth icshtheconduitsAsthern snlt li -ef icien ccolinssan :stabiiiza ionzofthe-stew .nerat r.- -theres stanc iliquidiee fectedcmerely 2h e li thntherataofpireulation of.thercoolant inuid. rand zits sentence:temperature. ari usaconnectionszt sa-nrie ntrchiorrth itwc iliqridsvwt. -.the dmamcmete saresshownzimthe a e liii a -yinsdrawinsssionccmnleteness'of illu ctratich vtheyihare littleprmhearin .onthe sa casm; v don-- iln'crcler ztoga lordasclearer oin'derstandinesorthe-construction:andzon raticn iitzzmey be znnintcdrpu that:therresistanceswater ri flischarsedsforzinstancesat25,zth rbafli izzand"pa sa e e2theins-pmittedeinsthis :nar ieular cup. flh 'inl t fclresistaricc:water.is. nothereinrsh wn. i'lhrrm lan is: dmittedmnonerside.iofethezstator, rasx'foltimstancek5,:and:discharges;;at::theroppo- ZSitBrSidCn at 46, aandlatreachrsuch:connectionefi and rlicthe assage is is :-omitt d :completely- 'Ainisiadmitted-or aiischareedipastva control valve 55 through i-the :nozzles.55, ;,=a-nd :a thermostat sensesrthetemperature :of:the:;:resistance:liquid-i to control various {operations such .:as therapidity :of sflow through ofz-the coolant within ;or-.:ficwing to orfrom the conduitss lsin:amannerxmorewiinllyset,for.th,-in,vari,ousvfqrmspr arrangements in the copendingapplication Serial No. 649,967. These devices and controls are not partof the present invention,=*but are illustrated for completeness and toshowithe-manner inrwhichithey cooperate withoninterfere with thejullutilizationofthe present inve Becauseit is necessary art-times towithdraw resistance gliquid from the .casi rig 1 duringoperationaforexample, in order.,to,vary= the resistance crzll ad-witnecessary tminsur t at themesistance liquid has adequate access to theoutlet 25. The coilsrdgmustbejhfildfbitfipacers 40 against excefisivevibration, andthese spacers tend to intercept ,and hold hackperipheralflow, of ,resistance water. "If a spacer :40 were located, close,tothemptlet -25, desired outflow of resistance watepwqflld be impededor'blockeid. According y, the spacers 40 are om'itte'd,in thedirectionof "rotation, for some distance ahead of the outlet 25 (seeFigure 3), and the outlet 25 is located just ahead of the headers 4|,42. The result is, the water attains peripheral momentum towards theoutlet 25, which is checked by the headers, and a pressure head is thusbuilt up at the outlet. When the valved outlet 25 is opened, evacuationof resistance water is prompt, because of this pressure head.

I claim as my invention:

1. In a Froude type dynamometer, a liquidcontaining vaned stator casingand a complementally vaned rotor, a coolant-liquid-filled conduitdisposed within the stator casing circumferentially about the rotor, andthe rotor having means for directing at least part of the resistanceliquid over said conduit prior to its rejoining the remainder thereof,for transfer of heat from the resistance liquid to the coolant liquid.

2. In a Froude type dynamometer, a liquidcontaining stator casingradially vaned to define stator cups and a rimmed rotor complementallyradially vaned to define rotor cups cooperative, when the rotor isrotating, with the stator cups to produce toroidal circulation ofresistance'iliquid, a coolant-,liquid-filled conduit disposedperipherally within the stator casing circumferentially about the rotorsperiphery, and means in said raiwo iticniliin iinea horizontal manerccmmonito thatwfl 'errim of he rotoretnniirecttasncrticnrcfsthe:resistance liquiu frem 'rtherrotcrmpsmcntinuously over the coolant-filled .coniduitriorstransierence ormeat therebetween, :rand thenqehbackaztorrejoin and cool the toroid ally'circniatingrresistanceiliquid.

. 213'. am iaiEroudettype wdynamometer, aa =1iqu idccontaimng vanedistator 1 casing and -a complementally :jvaanedcsrotor providing =-atoroidal circculation ,zspath, :sza ccoolant liquid-filled =condu-itdisposed iperil:laterallytwithin the --=stator easing :ae'diacentrtherrotorts-mperiphery; and means to'di- :ccct .rgatrlcast :aportion 1df= the :resistance liquid when d cenduit rforrheatexchange-'---therebeswa m ndlmeans etc induce fiow 4 of resistanceiliquid afterrbeingethusr'cooled, away -=from "said :QOR'QIMHJ,itandsinto the-steroidal circulation path.

9.4.1 In. a ifi'roudewstype dynamometer, '-a'-liquidcontaining :rvanedastator casing and -a complementallyarvaned water, a=:=codl-ant-l-iquid-Ffil-led zconduitidisposedrabout therotor speriphery,'-but twithin ttheszcasing, flthe -rotor s periphery *havingis plurality-cot :liquids discharge apertures spaced about; it, :anddirected towards said conduit, "for iizischargeiofrazportion only ofthecirculating rezsistancejfliquidroverithe conduit, and forextracationiiofiheatigrromcsuch resistance liquid.

1; In :a z-l'aroude-etype :dyn-amometer, a --',liquidcontaining vanedstator casing and a 'compleamenta'llyivanedrrotor acoolant-l-iquid-filledcon- :duitrdisposedabout the rotors periphery,"but :svithinrthe casing, the rotors periphery 'having :a plurality-10fliquid :discharge apertures *spaced about it, and directed-towardssaidconduitflfor dischargerofsarportion-onlyofthecirculating-rezsistanceirliquid cvser the conduit, and 'forextraction 40f :rheat ifrom such :resistance liquid, andaneanswactirated rby the normal internal circulation tzofzthe resistanceI liquid for inducing flow 10f .gresistancei liquid away from saidconduit.

16. In ea "Froude I type 1 dynamometer, a liquidcontainingnstator 'andwarotor therein; the stator and rrotor-kbeingcomplementally radially vaned,to iprovi'de rcups ffor toroidal circulation of resistance lliquid:within "the: casing, a coolant-liquidefilled i'conduit peripherallysurrounding the rotor within the stator casing, the rotors peripherybeing apertured at intervals for discharge centrifugally of resistanceliquid over said conduit, and a baflie spaced from the outer Wall of thestators cups to define therebetween an ejector passage leading from theconduit space to the toroidal circulation space, and shaped and locatedrelative to the rotors cups to receive discharge therefrom and to directthe same radially inwardly, as part of the principal toroidalcirculation.

'7. In a Froude type dynamometer, a rotor having radial vanes definingcups, a stator casing surrounding, and spaced distantly from theperiphery of said rotor to provide space for coolant conduit means,coolant conduit means in the space between the rotors periphery and thestator, the stator being vaned similarly to the rotor, to define cupsterminating at their outer ends beyond the rotors periphery and incommunication with the conduit-containing space, and bleed ports in therotors periphery for discharge of a part of the resistance liquid fromthe rotors cups into the conduit-containing space.

8. In a Froude type dynamometer, a rotor having radial vanes definingcups, a stator casing surrounding, and spaced distantly from theperiphery of, said rotor, coolant conduit means in the space between therotors periphery and the stator, the stator being vaned similarly to therotor, to define cups terminating at their outer ends beyond the rotorsperiphery, in communication with the conduit-containing space, bleedports in the rotors periphery for discharge of a part of the resistanceliquid from the rotors cups into the conduit-containing space, and abafile spaced from the outer wall of the stator cups, and curvedinwardly from a terminus adjacent the conduit-containing space to abafile between the several stator vanes, spaced from the outer wall ofthe stator cups, and curved inwardly from a terminus overlying butspaced outwardly of the rotors peripheral rim to 2. terminus adjacentbut spaced axially from said rim.

10. A dynamometer as in claim 9, wherein the spacing between the bafileand the walls of its stator cup varies from a wide entrance, adjacentthe conduit-containing space, to a narrow exit adjacent the rotorsperipheral rim.

11. In a Froude type dynamometer, a rotor having radial vanes definingcups, a stator casing surrounding, and spaced outwardly from'theperiphery of, said rotor, a pluralit of coolant-filled coilsperipherally surrounding the rotors periphery, in such space, spacers atintervals embracing the coils to restrain their relative movement, thestator being vaned similarly to the rotor to define cups complemental tothe rotor cups, for toroidal circulation of a resistance liquidcontained within 4 the stator casing, a resistance liquid outlet 10-cated in the coil-containing space, and bleed ports in the rotorsperiphery for discharge of a part of the toroidally circulatingresistance liquid into the coil-containing space, the coil-restrainingspacers being omitted, in advance of the resistance liquid outlet, tofacilitate peripheral movement of resistance liquid towards said outlet.

12. In a Froude type dynamometer, a rotor having radial vanes definingcups, a stator casing surrounding, and spaced outwardly from theperiphery of, said rotor, a plurality of coolant-filled coilsperipherally surrounding the rotors periphery, in such space, spacers atintervals embracing the coils to restrain their relative movement, thestator being vaned similarly to the rotor to define cups'complemental tothe rotor cups, for toroidal circulation of a resistance liquidcontained within the stator casing, a resistance liquid outlet locatedin the coil-containing space, bleed ports in the rotors periphery fordischarge of a part of the toroidally circulating resistance liquid intothe the coil-containing space, the coil-restraining spacers beingomitted, in advance of the resistance liquid outlet, to facilitateperipheral movement of resistance liquid towards said outlet, and aheader for said coils disposed immediately beyond said outlet tointercept peripheral movement of the resistance liquid, and to build uppressure in the vicinity of said outlet.

HAROLD L. BENNETT.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 2,164,173 Durrell et a1 June 27, 1939 2,358,825 Pribula Sept.26, 1944 2,361,726 Weimar Oct. 31, 1944 2,425,171 Bennett et al Aug. 5,1947 2,428,005 Bennett Sept. 30, 1947 FOREIGN PATENTS Number CountryDate 307,022 Great Britain Aug, 15, 1929 466,436 Great Britain May 28,1937 75,955 Austria Mar. 26, 1919 316,482 Italy Apr. 7, 1934

